Do your homework before choosing cotton varieties

In the future, technology which will help control glyphosate-resistant Palmer pigweed will drive variety selection.
Regression analysis of yield data, or comparing a particular variety to an average yield at a location can provide cotton producers with a better idea of how a variety performs in high yield and low yield environments.
A third of the cotton budget may be spent by the time cotton is planted and to the 2- to 4-leaf stage.

Choosing cotton varieties for your farm is like putting together a good football or basketball team. You need some bruisers, a few speedsters, a couple of all-round good players and one or two guys with a special talent.

“We’re not just planting a seed anymore.” Barber said. “We’re delivering a lot of technology to the field in that one activity, with the traits and whatever crop protection products are on the seed. One thing is for sure, we are much more front-end loaded than we used to be. A third of the budget may be spent by the time we get cotton planted and to the two- to four-leaf stage.”

Barber says under some circumstances in variety selection, growers are willing to sacrifice yield for the simplicity brought by a transgenic trait.

For example, data showed that in Louisiana, prior to the advent of transgenic cotton, over 50 percent of the cotton varieties planted in the state were either recommended varieties or in the top 25 percent of the official variety trials (OVTs). After the introduction of Bollgard and Roundup Ready cotton, producers planted many varieties that were not in the top 25 percent of the OVTs, which Barber says was due to the convenience of the new technology, plus the lack of strong yield potential in transgenic varieties at that time.

“When DP 555 BG/RR was introduced in Louisiana, the percentage (of varieties planted that led OVTs) increased,” Barber said. “I suspect that in the coming years (with DP 555 BG/RR phased out), the percentage will again be lower in Louisiana because a lot of the varieties that replaced 555 are not yielding as well in some locations.”

In the future, Barber says, technology which will help control glyphosate-resistant Palmer pigweed “will drive variety selection, especially in Arkansas.”

Cotton producer and ginner John Lindamood, who farms 3,200 acres of cotton near Tiptonville, Tenn., says the No. 1 factor in variety selection is relative maturity.

“We have to have short-season varieties, because we’re so far north. We plant a few mid-season varieties early, the first 10 days of planting. Then we have to go to short season varieties.”

Lindamood also looks closely at a variety’s seedling vigor “because we have cold, wet soils under no-till.”

Yield is an important factor for cotton producers, but Lindamood considers yield consistency and how varieties perform on soil type and across environments. “Over the last few years, we’ve been paying more and more attention to that, and we’ve seen our yields improve dramatically.

Grade and quality

“Grade and quality are also important because these factors can affect a large portion of price depending on premiums. But at 90-cent cotton, all of a sudden yield moves back to the forefront.”

Storm resistance is also important for Lindamood. “This past season was wonderful for harvest. Everybody talked about how one variety would pick well while others were tagging. It’s important to remember that those same varieties that picked clean this year, were stretched out and falling on the ground last year. We don’t want to put all our eggs in one basket. We want to plant some cotton that is going to hold onto the plant.”

Herbicide traits found in LibertyLink or WideStrike varieties can be overriding varietal factors for many cotton producers, especially where there is resistant pigweed. But Lindamood doesn’t rely on them exclusively.

“We can control pigweed with other strategies. We do have to look at the effectiveness of those products, and what damage we can expect to see in crops.”

OVTs are a good source of information, Lindamood says. “They are organized, viable, collected on time, analyzed for both yields and grades, and collected over multiple sites. The weakness is that the soil type and environmental conditions may be different from what we experience in our area of the state.”

For that reason, it’s important to have variety trials on your farm, set up by universities, seed companies or your Extension agent, Lindamood says.

“What we’re striving for is to plant varieties where we can push the yield on our strong soils under irrigation and maintain our yields on marginal ground. We don’t need to be planting racehorse varieties on marginal ground. We need to plant varieties that have the best chance of success.”

Regression analysis of yield data, or comparing a particular variety to an average yield at a location, provides Lindamood with a better idea of how a variety performs in high yield and low yield environments. “A variety like ST 4554 B2RF has been a staple for us. It’s very consistent across a range of environments. PHY 375 WRF has played a big role in controlling pigweed.”

Seed company representatives are another source of information for Lindamood. “They have a thorough knowledge of their own varieties. They can aid in placement of those varieties.

“Obviously, they have a vested interest in selling as much seed as they can. Certainly they’re not going to misdirect your efforts, but if you rely too heavily on them, you can find yourself loaded up on one variety or another, and you may not have enough diversity. But once you know what you want, they are an excellent source to help you decide where to place those varieties and how to match them to your soils.”

Lindamood says crop consultants “bring a tremendous amount of experience to our farm. They can help select and analyze data to help us make the final variety selection.”

Lindamood says about 70 percent of the cotton varieties on his farm “are planted historically, and we know how they’re going to perform on selected environments. We leave room on about 30 percent of our acres to look at what’s coming out from the universities and coming down the pike from seed companies.”